In the Renaissance, painters were so impressed with Leonardo

Narmadadhruv and RMD007 and rohitmanglik -- ugh, that's not a very easy question. Which makes it a really good question.

In general, the GMAT isn't completely clear about the "so...as" idiom. There are very few official GMAT questions that feature this idiom in a correct answer -- and for whatever it's worth, I don't think that the SC question in this thread comes from an official source, either. So don't worry too much about this particular case, but I'll do my best to break down the variations on the idiom so that you can understand it in general.

The GMAT is clear about the following:

• "so as to x" (without any words inserted into the idiom) is considered awkward and unidiomatic; see OG 12 #39 & #65 for examples (also here and here, though the official explanations aren't usually included in the GMAT Club threads)
• "so x that y" can be correct, as rohitmanglik mentioned in #4 above: "I drank so many shots of espresso that my heart exploded... ; see OG 12 #37 (here on GMAT Club)

Taking the other three variations one at a time:



I don't think that "so X as Y" is really an idiom that you need to worry about. The question in the link is OG 12 #76, and the correct answer looks like this:



The "so bad as" isn't really an issue at all. The key here is the comparison, "as much because X as because Y". It's coincidence that there's a "so" inside the comparison in this particular question. If you're treating "so bad as" as an idiom in this example, you're missing the heart of the question.



I don't think this is ever correct, but maybe I'm just not being creative enough -- perhaps there's a way to tweak "X" and "Y" to make it work. At the very least, I can't think of many official GMAT questions that really test this.



The link is to an irrelevant quant question... but check out this one instead: https://gmatclub.com/forum/often-major- ... 74856.html. In the OA, "so gradual as to be indistinguishable" is in the correct answer. So it seems that "so X as to Y" can be OK.

The only trouble is, here's an OG question (OG 12 #37, OG 13 #39) with the same construction: https://gmatclub.com/forum/although-sch ... 99143.html. And here's a direct quote from the OG explanation:



So... yeah, the GMAT is confused about it's own rules here. I'd be wary of the "so X as to Y" construction, but the GMAT can't decide what it thinks about it, so there's no hard-and-fast rule.

To summarize: "so x that y" can be correct; the others are suspect at best. And this is way less important than some other things in SC!